Atmospheric Stability: Why Not All Wind is Born Equal
(Room Jupiter 8)
03 Sep 15
9:00 AM
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10:30 AM
The global growth of onshore wind is increasingly being driven by emerging markets that are characterized by wind regimes that are different in nature to the meteorology of the mid-latitude markets that historically have driven the development of the industry . Wind regimes in emerging markets are broadly characterized by lower annual mean wind speeds and in response, wind turbine technology is evolving towards the use of larger rotor diameters at higher hub heights in order to exploit the available wind resources. However, these wind regimes also characteristically feature large diurnal variations in atmospheric stability and in such conditions it is important to understand turbine performance across a range of meteorological conditions.
DNV GL has observed that turbines can fail to meet warranted power curves within stable atmospheric conditions defined as having low turbulence and high vertical wind shear. The issue is exacerbated by emerging wind regimes and with modern technology development. DNV GL investigations indicate that additional calculations must be undertaken in order to accurately predict wind farm output. Furthermore care is required in the contracting of warranty provisions to ensure that any variations in performance can be measured and accounted for.